1. Field
The present invention relates to a new and quick method and apparatus to achieve bypass grade filtration in equipment using the widely known spin-on oil filter, where installation time is dramatically reduced and simplified, with no modifications, fewer parts, and lower weight.
2. Description of the Related Art
Bypass filtration is a well-known field and many devices have been proposed to achieve fine oil filtration. Engines, and other industrial processes, require for their proper performance and longevity a degree of oil or hydraulic filtration that is a compromise between the size of the particles to be captured by the normally provided filter and the required flow of the fluid for the proper performance and longevity of the machine or system being protected. In automobiles, there is regularly only a motor oil filter described as a full flow filter. The full flow filter must flow an adequate oil volume and therefore the size of the particles that it traps cannot be too small or the risk of starvation of lubricant to the engine is a possibility, with catastrophic consequences to the engine. Therefore, most full flow filters, be it canister type or spin-on filters, trap particles in the order of 25 to 40 microns in cross section and above in an efficient manner. However, studies have pointed out that particles in the range of 2 to 25 microns are the most harmful to the engine due to the thickness of the lubricating film between rotating partners in an engine.
It is now apparent that in order to stop the mechanical degradation of an engine, the particles that the full flow filter does not trap must be removed by other means since in the presence of the full flow filter these particles move around the lubrication system unfettered and behave like liquid sandpaper with respect to rotating partners in an engine. In addition to the mechanical degradation caused by these particles, some particles are actually damaging to the lubricant in question degrading the additive package that renders lubricants ineffective in protecting the engine and its components. These additives get depleted because contaminant particles react chemically if they are left in suspension and dispersant additives are taxed by their presence, and these result in increased viscosity of the oil where parasitic pumping energy and rotational energy losses are increased accordingly. Yet another mode of degradation is the reaction of these particles that create acids and deplete the additives degrading what is widely regarded as an indication of the health of the oil, the Total Base Number, or TBN, which is a measure of how well the oil would protect the engine against the presence of acids in the oil. These acids eventually damage parts by pitting the working surfaces, among other damages.
The advent and increasing popularity of Diesel makes this type of filtration much more attractive since Diesel pollution controls relies on a process known as Exhaust Gas Recirculation, or EGR, in order to control the amounts of tailpipe emissions. This process, although effective for the control of pollution, taxes the oil by loading it with soot particles that find their way to the lubricating oil by means of blow by around piston rings of an engine, increasing oil viscosity and accordingly, parasitic energy losses. It is clear that the current filtration left alone to the functions and capabilities of the full flow filter leaves much to be desired and that an additional filtration device is needed in order to protect the machinery and systems that are being lubricated. A way to protect against this shortcoming is by the use of bypass filtration.
Bypass filtration is a proven and effective technology where a portion of total flow is diverted from the full flow filter and passed through a filter that has a higher filtering capability and then returning it to the engine or system usually to the crankcase or oil filler cap in a vehicle. These systems are popular in big rigs, or class 8 vehicles, in spite of being costly, difficult to install and maintain. However, the payback of such systems is assured considering the investment and the benefits returned due to their high mileage accrued during operation, which can be in the order of 100,000 miles in a year and even more in some cases. Passenger vehicles are not widely equipped or optioned with these systems because of their cost, complex installation and maintenance. However, the benefits of Advanced Filtration, researched by the US Department of Energy through the Argonne Laboratory, SAE and others, yield an impressive array of benefits, among them: oil life extended up to 10 times, oil filter full flow extended from 3 to 5 times, emissions reduced by up to 15% due to reduced friction and parasitic energy losses, and fuel efficiency increases in the order of 3 to 5% are cited. In addition to the benefits described above some other important benefits are less engine component wear with lower overhaul costs, a better performing engine over its operating life, vehicles with better resale value, and when adopted in great scale it would benefit our country's position with respect to foreign oil dependency. In spite of all the benefits, the complexity of installation and its cost are the main reasons why this current technology is not widely implemented in vehicles used by the general public and government fleets until the advent of the present invention where the cost of manufacture and installation has now been dramatically reduced.
The current methodology of connecting a bypass system is first connecting it to the oil pressure supply in an engine, usually found through a “tee” connection at the oil pressure sending unit. In some cases, this process requires a great expense since the oil pressure sending unit is usually buried right beneath the intake manifold in most modem engines, and even in older engines it is in a most remote location, making searching for the “tee” and plumbing of the system a costly and labor intensive proposition. For illustration purposes, in my personal car, a Porsche 911 SC, in order to gain access and “tee” off the sending unit, the whole engine and transaxle must be dropped at a high cost that may not justify the benefits of the installation of a bypass filter system. In addition to that, the return of the purified oil, once the pressure side has been secured, must be done through modifications either to the sump plug at the bottom of the engine, which complicates future oil changes, or return the oil through the oil filling cap, again requiring modification and possible release of contaminants to the environment through shoddy installation.
The present invention solves all problems mentioned above through a method and apparatus where installation needs no modifications to the engine and connection time of the system has been recorded to be less than one minute, with a full installation requiring a bit more time. As can be appreciated, there is a significant body of prior art in this field that has been built over many years to achieve bypass filtration to engines and systems, representative of this prior art are the following US Patents: U.S. Pat. No. 4,452,695, to Schmidt for a full-flow and bypass filter conversion system for internal combustion engines; U.S. Pat. No. 7,090,773, to Meddock and Swanson for a Coaxial full-flow and bypass oil filter; U.S. Pat. No. 6,951,606, to Cousineau and Allen for an Auxiliary filtration system. More illustrative examples for combining full flow and high density filtering have been integrated in one single unit, such as shown in Dahm, et al., U.S. Pat. No. 4,036,755. However, such a filtering system is not made in such a manner that is easily connected to the standard engine filtering system. Also, the high density portion of the filtering would only operate for a much shorter period of time before it would become clogged and the entire flow would then flow through the full-flow portion. Upon clogging of the full-flow portion, the by-pass valve would open and the oil would receive essentially no filtering. The same basic comments are true concerning Belgarde, et al., U.S. Pat. No. 2,995,253. Likewise, Beardsley, U.S. Pat. No. 2,680,520 shows a full-flow and part-flow filter combination. It has the same inherent problems as the previously described full-flow and part-flow filters. These problems may be exhibited by a recently developed combination full flow and a bypass grade Teflon sintered disc, with a rather small loading area for the bypass section, generously estimated to be limited to a cross section of the filter, such as U.S. Pat. No. 6,605,215, to Assion for a Hybrid spin-on oil filter, and U.S. Pat. No. 7,048,848, to Assion for, again, a Hybrid spin-on oil filter. These two patents describe a laudable and ingenious interpretation of an old idea whose execution fails to recognize the increased loading of contaminants and the small loading and service capacity of such, while still not fully addressing the environmental impact inherent in spin-on oil filters related to their illegal dumping and disposal. Yet other examples such as Kennedy, U.S. Pat. No. 2,843,268 is simply another variation of the combination full-flow, part-flow filter that also has the problems of life cycle and the pressure drop that can be utilized in the filtering system itself Belgarde, U.S. Pat. No. 2,929,506, is simply another modification of the combined full-flow and part-flow oil filter. Allen, U.S. Pat. No. 2,966,269 again shows a combined full-flow and by-pass filter with strainer mounted in one single contiguous housing with only one by-pass valve.
Other examples can be found in U.S. Pat. No. 6,666,968, to Smith et al. for a Fluid filtration apparatus; U.S. Pat. No. 5,843,284, to Waters et al. for Two-stage oil bypass filter device, and U.S. Pat. No. 5,695,637, to Jiang et al. for a Combination full flow and bypass filter with venturi nozzle.